• Khoa hpc Ky thuit vi Cdng nghi Phan lap va tuvin chon chiing vi khu^n CO kha nang khii mau nu oc thai det nhuon %;;„>;„ Hi>v I huJM Nsu>fn \ i n Clang" U Thj \ i n Anh j,„ „ , Ij •'''' , 1,'''' Ihnms A" ''''[.]
• Khoa hpc Ky thuit vi Cdng nghi Phan lap va tuvin chon chiing vi khu^n CO kha nang khii mau nu-oc thai det nhuon %;;„>;„ Hi>v I huJM Nsu>fn \ i n C l a n g " U Thj \ i n Anhj,„ „ , Ij: _•' , 1,' Ihnms A " ' « " • ' ' • " '•'" r \.eyr i:hu\cn plian hit" iil'J, n^av nh3iiplia ,1,1 ••„ io i::oi".ns3>ii"n'*••'"'•'"*•' ^^"^""^ ^ - - - o n h i l n , moi t r u i g u g h i e m t r p n g Nhi^u Nude Ihai d?t nhuym khong qua \ir h \ a Ir^rc tiep vao nguon niro-c SL g.iv o ntiiem ^^^ ^,_^ ^^^ ^^^.^^ ^ ^ ^ ^ phirmiH p h i p V Iv hoa h^>c n h « Ipe kit tua keo tg 6k dirge tien hanh luv " ' " ^ " -'• j ^ ^ , ; ^gt „ h u m d u g c hr^nif; lao raclKii thai x u l v anh h t n m s ldi hv sinh thai .Sir dung viMUh vat a e ^ ^ ^ ^ ^ xem h phutmn phap thav thi^ v gia khimg cao than ihien vdi mm irirotig Nh.eu chun chi vi k L a n vi n i n va k h u i n v ,a eo kha n n g phan huv ,hu6c nh.i(MU Nghien eiru ^ ' ^ ; ' ' ^ ^ ^ ^ ' ' ' ^ " j ; ; , ^ i dich khao kha nang k h u mau thuAe nhunm Red I N : H eua mC- sA chung vi khuan d u p e phan ^ ^ P * Y " " ' * , ^ d( nhtii.m, Ba ehung vi khuan v:, ^9 ^ VI4 eo hi^u qtia k h u mau da dugc tuven ' = ' ' " : " f " / ! ? \ ^ , ^ ™ ' " ' ehung V (S.),.," i - M4 ^iC.S-'.^ - M (.M.6%) rongdic^u ki^n nuoi tinh; di^u kifm nuot lae, h u q u a p h a n huy th.n'.c nhupm eua chung V> (fi.V^- l M4 (34,9".,,> V2 ,26.9%) C h u n g Vi dupe ehpn de khao s^t a n h h u O n g cua mi}l si, dl^-u kivn moi inning nuoi eav Mi^u qua k h u mau eua chung \ manh nhk mot truffng n u o i cay CO nguon earl.on la tinh b(.l nguon nito-la (NH.I.so^ \ H , ( I hav cao nam men, mat dp vi khuan 5-15/«, pH mot truiyng i n m g khoang (.-^, nhipl dg 35 < C \9 et liim n.ing tmg dung \u- Iy nir6e thai det nhupm Ill khmi khir mdu nutre thai, phan huy sinh hpe Ihuoc nhupm Chi sd Khan loai: 2.^ B«trtndA Trong nganh cong ngluep del nhugm hang nam khoang 200.01)0 tim ihuoe nhupm cac loai dupc thai ducn dang niroc thai qua trinh nhugm va hoan lhi?n san pham (I ] Phan Ittn cac loai thuoc nhugm ton lai rat lau lu nhicn linh on djnh cio cua chiing doi voi anh sang, nhiel dp Xa tare liep mrac ihai tir qua trinh del nhupm in vao nguon nuoc se gav nhiem nghiem Thutjc nhuom irong nuoe lam t.^ng dg due khong chi gay giam dp lioa tan o\v nuac ma lam g u m kha nang \u>en qua nuoc cua anh sang m^l ircn, da anh huong den quang hop va loan bg he sinh thai duai nuac [2] \ a nuoc thai del nhugm vao JO song e lam ihav doi pH va tang nhu cau o w sinh ho.i, nhu c.iu oxv hoa hoc va long carbon huu ca [?] Moi Ml tluiiv nhupm nhu ayo va cac ^an pham phan huv chung CO null diV CO kha ri.ing gav ung thu anh huong tai sue khoe ngiiai Miicu plurong pliap \,\i K, hoa hgc nhu ivv kcl lua keo ly d.'i duge licii hanli luv nhien gia CIO lieu thu nhicu nang Iuang, lao that thai kho xu K ciing nhu anh huitng tai he vmh ihai [4 S] I'liucmi; phap sinh hi,H.- duoc \em la giai phap ihav ihe hicu qua vi iiia khong eao, than ihien vai moi trtriTng \iNCNG«\iet V:!" iren smh kh6i vi smh vat hay phan huy sinh hgc bai Ic bao VI sinh vat [I], Hien nay, bien phap phan huy sinh hoc dugc img dung de loai bo nhieu chat gay nhiem Nhieu loai vi sinh val, gom vi nam, vi khuan, vi lao, nam men co kha nang loai bo nhieu dang thuoc nhupm [6] Cac loai vi sinh V at sinh long hgp nhieu enzyme can thiet cho qua trinh lam mat mau va khoang hoa thuoc nhugm cac dieu kien moi inrcmg thich hgp [4] Tren c a sa do, nghien cuu dugc lien hanh voi muc dich phan lap, tuyen chgn chung vi khuan tir nuac thai lang nghe del nhupm va khao sal anh huong cua mgl so dieu kien moi Irucrng toi kha nang lam mat mau thuoc nhuom Irong dieu kien in vilro Vdt lieu va phUfTng ptiap ngtiien ciia i'di lieu Trong nghien ciru thuoc nhuom Red FN2BL i Reactive dye) vai /.-526 nm da duoc su dung, Niroc thai del nhuom dune lay tu lang nghe del nhuom phuong Van Phuc quan Ha Dung P Ha Ngi Sang loc Idn ddu < a• chung vi khudn khir mdu ihudc nhudm Phan lap \ i khuan lu nuoc tliai del nhuo" Khoa hpc Ky lhu$t vd Cdng ngh$ i bang each pha loang mau nuoc thai nuoc cat v a ca\ chang tren dTa thach dinh duong Cae dTa th^ch dugc it 37-2T 24h Nhung khuan lac vai hinh thai khac dugc lach rieng va nuoi cay lam thuan [7], Cac mau \i khuan sau da duoc lam thuan dugc nuoi eav moi truong dinh duong long NB (gom (g/l): Peptone 10 Beef exU^ct 10 NaCl pH-7.3±0.l) 24h Iruoc ca\ ehuven sang moi trucmg muoi khoang loi thieu (gom Huy Thuan Nguven' Van Giang Nguyen'" (gl): (NHJ.SO^ ICHPO^ 1, KH,PO, MgS0,.7H,0 Thi Van Anh Le* 0.1, NaCl 5."glucose 3^ nuoc cdt 1000 ml pH-7) Sau 24h 'Instilule of Research and Development Duy Tan Universit} nuoi 10% (vv) dich nuoi cac chting vi khuiin dugc chuyen •Faculty of Biolechnology yielnam National Universm- ofAgriculture sang ong nghiem co chira 200 mg/l dung djch thuoc nhupm Received 22 October 2019; accepled Januarj 2020 Quan sat su khir mau ciia cac chung v i khuan sau 4Sli ii cac ong thi nghiem a 30±2°C, Chiing nao bieu hipn liem nSng /tbstract: khir mau manh nhal dugc chgn de tien hanh cac thi nghipm Directed discharge into water sources of untreated textile tiep iheo [8] dyeing wastewater will cause seriously environmental Sdng lpc ldn cudi vd ddnh gid hi^ii qud khir mdu thuoc contamination Various kinds of physico-chemical methods have been in use for the treatment of the nhuom ciia cdc chung vi khudn phdn Igp wastewater However, these methods are not environment Thi nghiem dugc lien hanh bang each sir dgng friendly and cost-effective, and hence become thuoc nhugm Red FN2BL moi truang MS king commercially unattractive Many microorganisms Moi chiing vi khuan dugc chpn dugc nuoi 24h irong moi strains belonging to the different taxonomic groups truang NB, sau chuyen 5% (v/v) ciia moj chung sang of bacteria, fungi, actinomycetcs, and algae have been binh Erlenmeyer(V=250 ml) chira 50 ml moi truirng MS va reported for their ability to decolourise dyes This study 100 mg thuoc nhupm Red FN2BL Cac binh sc dugc was conducted to investigate the decolorisation of Red nuoi cay a 30±2°C, thai gian 24-72h, dieu kign tmh FN2BL b\ using bacterial strains isolated from textile va lac (150 vong/phiit) Dp hap thu anh sang cua cac mau dyeing wastewater Three different bacterial strains ihi nghiem dugc tai ?t=526 nm a thai diem 24 va 72h [8], A2, A9 and A14 exhibited high decolorization effects Dua tren ket qua giam dg hap thu, % khir mau thuoc nhugm were selected Decolorisation effect of strain \9 was dugc linh loan, chiing vi khuan co liem nang khir mau thuoc 80.6%>A14 (67.5%)>A2 (34.6%) in stable cultural nhugm cao se dugc chpn cho cac thi nghipm lii}p theo condition and was A9 (63.3%)>A14 (34.9%)>A2 (26.9%) Hieu qua khu mau thuoc nhupm dtrpc bieu hipn bang %, in shaking cultural condition The strain A9 was selected for evaluating the effects of some cultural conditions ml mau thi nghiem da khir mau dugc ly lam 10.000 vong/ Strain A9 showed maximum decolorisation ability at phiit 15 phul va do hap thu anh sang lai X=526 nm, pH between and 7, temperature of 35''C, and bacterial Ong doi chimg chi chira thuoc nhugm va moi truang nuoi density of 5-15% Starch and (NH^),SO^, NH^Cl or chung vi khuan Thi nghiem dugc lap lai lan Hieu qua yeast extract were found to be the optimum condition loai bo mau cua cac chimg vi khuan ihi nghiem dugc xac for decolorisation In brief, the strain A9 reveals a great dinh theo cong thirc sau [8]: potential for application in the textile dyeing wastewater Hieu qua khir mau (%) = [(1 - F)x 100]/1 fl) treatment Trong do: I la hap thu ciia ong doi chirng; F la dp hap thu cua ong thi nghiem Keywords: biodegradation, decolorisation, dyes, Khdo sdt dnh hir&ng ciia mpt so chi tieu den khd ndng wastewater khir mdu cua cdc chiing vi khudn thi nghipn [5] Classification number: 2.7 Anh hirijng ciia nong ihuoc nhupm Red FN2BL: cac chiing vi khuan ihi nghiem dupc nuoi 24h moi trucmg NB sau 5% (v \) dich nuoi vi khuan duoc chuyen sang binh Erlenmeyer (V=250 ml) chira 50 ml moi Iruong MS dugc bo sung 100, 200 va 300 mg/l thuoc nhugm, pH=7 Cac binh se dugc nuoi cay 30+2'X', irong thoi gian 72h dieu kien tmh Hieu qua khii mau dugc linh iheo cong thuc (i) Isolation and characterisation of decolorising bacterial strains isolated from textile dyeing wastewater f t vi Cdng nghi Anh hmmg cuu n Ic licp giong cac chung \ i khuan tin nghK'm dugc nuoi 24h moi truiTie NB *au lan lugt bo sung VI khuan a cac nong khac nhauiv v ): 1,5 10 va 15'V vao binh Frienmevcr i \ -25ii ml) cei chua 50 ml moi trutmg MS v a 100 mg I ihu.x: nhuom ehuan nioi tnn-Tic ve pH " Cac binh nav s2 dugc nuoi eav a 'ib2 C irong i h ^ gian 72h dieu kicn tinh Hi^u qua khu mau dugc tmh nhu cong thuc 111 Anh hmmg cuu pli nhi('i dd ac ehung \ i khuan ihi nghifm dugc nuoi 24h irong moi truang NB sau 5*^0 iv v i d)chnu6i vi khuan duoe ehuvcnvjo binh Frlenmc>er(\ -2>M ml) chira 50 ml moi truang MS duoe Ki sung ilKhiig ihuoe nhugm pH cua cae hinh ihi nghiem duoe Jieu chinh dat s, t\ V J S Cac binh nav duoe nuoi e.'iv a 'Or2"C, ihai gian 72h dieu kii*n iTnh Tuong ty nhu va\ chinh pH eua hinh ihi nghidm de d^i gia in pH^ ~, nhung cac binh dugc u a nhiei 15, 25 30 v.i 411 t , irong ihtti gian "2h dieu kicn linh Hieu qua khii mau dugc tinh iheo cong ihirc (I) Uih hmmg cua ngudn carbon \d niiir cac chting \ i khu.in thi nghidm duoe nuin 24h irong nioi uvcmg NB sau 5"n (V V) djch nuoi vi khuan dugc chuyen vao binh Erlenmeyer i \ - ml) chua 5o ml moi truong MS dugc bfl sung 100 nig I thuoc nhugm, nguon ducmg glucosic moi inrone MS duoe Ihav ihe bang Saccarose, tmh bgt, Lacio-.e \vio-.e, Mallo-e va Fructose Tien hanh thi nghiem tuang Ur niurne ihav nguon (Nil i.SO moi Iruong MS b.ing NMC'l NaNO KNO \a peptone, cao thit, cao nam men Cae binh n,iv liuoe nuoi eav a 30±2''C, irong ihoi gian ~2h, a dieu kien tmh Hi^u qua khir mau duge tinh theo cong thirc (1), K«t Qua va tuat iBiB AW qud phdn lap chiing vi khudn tir niro'c thdi del nhupm Mpl so khuan lac eo hinh thai, mau sac khac da \uai hicn iren dia moi tiirang thach dinh duong sau de dia o 3"'C ,sau 24li (hinh I) Cac chung vi khuan phan lap lir niju nuac thai thu tai lang nghe del nhupm phuong Van Phiic quan Ha Dong TP Ha Ngi duoc ldn luot dat ten la AI d^nA14 Hinh V Khuin lac chung A2, A4 va A5 phan lap dugc \M nu thii d^t nhu^m KHOAHOC \ Nhieii nha oghien euu da phan '-'ly''-'' \\^^\:^x nhie-m ^ ^ ^ ^ j,^j^|^ M khuan khu mau nuac tha nhuoin [U^ thu.v nhugm azo [S] Kel qua cho ^^^ _^^ ^^ ^^.^ -^_^-^^ s6t irong nehi tu nhicn ciia cac chung vi khuan i-'v-rig hi nhiem ihuoc nhugm va Ktui n-in^- • dieu kiv'n CO thu6c nhugm dpc hai Sin, l,c lin Ma eae ehttn, vi ^httin ^"^ " ' ° " ' " " - nhupm a n u , C , „ , -.an D , ^ - ; ; - : : ^ r m l d,n., Jmic lam Ihuan Juoc nuoi ca> -41i tron^ ,^.°,„,,;;, d u ™ lone NI! iruac klu c.« chujcn sang nu>, tmcmg muo, khoan u-.; ,h,cu sau 24h nuo, 10% > > d,ch num ca C h u n ; , khuan dugc clunen sang ong ngh.em co chua 200 m f d u n g d,ch hu6c nhupm Ket qua khu mau cua cac ch'ung >, khudn sau 4Sh u cac ong th ngh.em a 30±2 C dugc the hi?n a hinh '7»-»^ .^ r EX Al v: AJ A4 A5 VG A7 A8 A9 A10A11 A I A Al Hmh 2, Ket qua sang Ipc cac chiing vi khuan co kha nang khumau thuoc nhupm, Kel qua quan sat cho Ihay, chiing A2, A9 va A14 bieu hien hieu qua khu mau thuoc nhugm manh nhat, d u g c chpn de lien hanh danh gia hieu qua khir mau thi nghiem liep Iheo Anamika va cs (2013) [8] cung da sang lpc dugc nhieu chung vi khuan co kha nang khtr mau mgt so loai thu6c nhugm nhu Balck WNN, Blue FRN, Blue RC, T U R Q blue, nhung chi sang lpc dugc mgt chiing vi khuan khir mau thuoc nhupm Red FN2BL la thuoc nhugm dugc sir dung u-ong thi nghiem Ogugbue va Sawidis (2011) [1] da niyen chpn dugc chiing vi khuan co kha nang khti mau thuoc nhugm Basic violet 3, Trong thi nghiem ciia minh, Ken Meerbergen va cs (201 8) [2] da tuyin chon d u g c cac chung VI khuan thugc chi Acinelobacler va Klebsiella biSu hien tiem nang khu mau thuoc nhuom azo Tu cac mau n u a c thai thu thap tai vimg bi nhiem thuoc nhupm Maulin va cs 12013) [4] cung da phan lap duac 50 chun;; \i khuin co ihe ;.v.i bo thuoc nhuom Nliu vdy co the ket luan rang, cac Chung vi khuan mai duoc phan lap tir nuoe ihai del nhuom CO the song \ a smh truong moi truong co cac loai ihuoc nhugm khac Khoa hpc Ky thuit va Cdng nghi « Sdng lpc lan cudi vd ddnh gid hieu qud khir mdu thude 72h nuoi cay voi cac nong thuoc nhupm khac nhau, hieu nhupm cua cdc chung vi khudn mai phdn lap qua khu mau ciia chiing A9 dat 76.7-81.3" a phu ihupc vao Chiing vi khuan A2,A9 vaA14 dugc nuoi 24h irong moi nong dp thuoc nhupm (bdng I), Khi tang nong dg thuoc trucmg NB, sau chuyen 5% (v/v) ciia m6i chiing sang nhupm, hieu qud khir mau ciia chting A9 giam Hi?u qua binh Erlenmeyer (V=250 ml) chua 50 ml moi truang MS va khu mau ihuoc nhupm ciia cac chiing vi khuan giam 100 mg/l thuoc nhupm Red FN2BL Cac binh se dugc lang nong dp thuoc nhugm da dugc nhieu nha nghien cim li tai 30+2°C, thoi gian 24-72h, a dieu kien tinh v a ldc cong bo, Saad El-Din Hassan vd cs (2015) [5] khao (150 vong/phiit) Hieu qua khir mau (hinh 3) ciia chiing ^9 sat anh huong ciia nong dg thuoc nhupm lot hipu qua khii (80.6%)>A14 (67,5%)>A2 (34,6%) diiu kien nuoi mau ciia cac chiing vi khuan Klebsiela da ghi nhan kel qua tmh, dieu kien nuoi ldc, hieu qua phan huy thu6c none dp thuoc nhupm tang, hieu qua khii mau cua cac nhupm ciia chiing A9 (63,3%)>A14 (34,9%)>A2 (26,9%) chiing V i khuan giam ro ret Nong dg thuoc nhupm Reactive Ket qua sang Igc cho thay, hieu qua loai bo thuoc nhugm ciia Black nhieu hon 200 mg/l da giam hieu qua khir mau ctia cac chiing vi khuan thf nghiem dieu kien linh cao hon chiing VI khudn Enlerohacler sp [11] Hai chiing vi khudn diSu kien lac Thi nghiem ciia Anamika va cs (2013) Enterococcus faecalis va Klebsiella variicola da giam kha [8] cung cho thdy, khd nang khir mau thuoc nhupm ciia cac nang khu mau Ihuoc nhupm tang nong dp thuoc nhupm chiing vi khudn dieu kien tmh cao hon irong diSu kien tir 50 den 100 mg/l [6] Nong dp cao cdc loai thuoc nhupm I5c Theo cong b6 ciia Chen va cs (2003) [10], vi khudn irc che kha nang loai bo mau lir ca chal ciia vi khudn vd anh Aeromonas hydrophila khir mdu thuoc nhugm (80%) huong toi sinh trucmg, trao doi chdt va long hgp enzyme ciia diSu ki^n tmh (ky hay higu khi) Wang va cs (2009) [11] te bao vi khuan [1.5] Cling ghi nhdn hieu qua khii mau thuoc nhugm ciia chiing vi khuan dat 96% dieu kien ky khi, va chi dat 13% Bang Anh huwig cua nong dp thuoc nhupm to-i khd nSng khi> dieu kien hieu khf, lac 150 vong/phut Tuy nhien, mot mau cua chung vi khuan A9 so ket qua nghien cicu ciia Ogugbue va Sawidis (2011) [ ], None dQ Ihuoc Gifi trj OD o, , • > Saad El-Din Hassan va cs (2015) [5] cho thdy, hieu qua khu nhugm (mg/I) Doichune ThinelxiSm mau thuoc nhugm ciia cac chiing vi kliuan thf nghiem cao a.209 0,039 nhat dieu kien hieu klii (nuoi lac), Nhu vay, hieu qua 0.694 0,151 khij mau thuoc nhupm cua cac chiing vi khuan khong chi 1.439 0.335 ph^i thupc vao dieu kien hieu klif hay ky khf, co the phy thupc vao cac yeu to kliac nhu khd nang sinh truang, long Anh Inrang cua ly le liep giong: hieu qud khir mdu thuoc hgp enzyme phan huy Ihuoc nhupm ciia chung vi khuan nhupm ciia vi sinh vdt phu thupc vdo nhieu qua trinh nhu phan huy sinh hpc, hdp phu sinh hgc, kel liia [5] Vi the, sinh khoi te bao co vai tro quan Irpng qua trinh khir mau nuac thai Ket qua thi nghiem ciia chiing toi (bdng 2) cho thdy, mat dp vi khudn tang tir den 15%, hi?u qua khir mau tang tucmg img tir 40,0 den 88,0%, Bang Anh hudng cua ty le tiep giong toi kha nang khi> mau ciia chung vi khuan A9 Ty 1? tiep giong (%) None 6^ ttiuoc nhupm ^'^ '"T OD £,^- ^hihtg ,, , u • * Thf nghidm Hinh 3, Kha nang khip mau thuoc nhugm ciia chiing A2,A9vaA14 sau 72h dieu kien ITnh (T) va lac (L), 0.130 40,0 0,039 81,3 Kit qua thi nghiem cho thay chimg vi khuan A2, A9 vd A14 la cdc chiing vi khuan ky klii khong bat bupc, oxy can thiel cho sinh trudng ciia vi khudn, nhimg lic che hieu qua khii mau ciia chiing Dua tren hieu qua khir mau, chiing A9 dugc chpn de lifin hanh cac thi nghiem tiep theo va dupc nuoi dieu kien tmh 0,035 B3.3 0,025 88.0 Hieu qua khir mau cao nhat (88,0%) dat dugc lugng giong vi khuan ban dau la 15%, Mohan vd cs (2013) [12] ghi nhdn chiing Bacillus sp, va Planococcus sp dat hipu qua khir mau cao nhal nong dp chung giong ban dau la 10% Khdo sdt dnh hirang cua mot so chi tieu den khd ndng va thap hon a cdc nong dp 1, vd 5% Ket qua tuong tg cung da dugc cong bo boi Kumar vd cs (2009) [13] khir mdu cua chting vi khudn A9 Anh lur&iig ciia nong ihudc nhuom Red fSlBL 4nh Inr&ng cua pH, nhiet do- pH ciia moi trucmg nuoi sau 55 I Khoa hpc Ky thuit vi Cdng nghi ni.nvaes.20.W,ll3]dncllu^nJojM^.^^,^, c^y dong vai tro quan Joi vm hoat dgng sinh 1> CI:J cue ti- bao VI khuan va >u trao doi cua cac phin dmh dm>ng kha^ qua mang Hi?u qua khu mau cua ehung VI khuan A'J Jai cao nhat lai pH=t>-" lane hay gum eia trj pH so vol -" hiv'uquakhumau deu giam ibang 'i "^.ud Fl-I)in Hassan va cs | ? | [5] da ket luan nine pH loi UL de d^i hii-u qua >.!•.: mau cao nhal cua chung vi kh ir Klcl">iclUi pneumoniae va A,' '•' lla \anicola la 5-" net likng hav g u m pH si> voi gia in nav hieu qua khu mau gi ' Mjiilin \.icst2013)14) trongthi nghiC'm cua minhd.l kl\'i"j dinh pH mid truong tang tu den " hieu qua klur mau ting va d.ii hieu qua cao nhal iJi pH " neu Hep tut i.ing pM loi 9, hiv'u qua khu mau giam Nghien cuu cua Kumar vj cs (200-)) \\\\ ken Meerbergen va cs |201 M [21 cimg cho kcl qua Urong Ig hii'u qua khu mau cao nhat cua hon ln,Tp vi sinh v,ii d.ii dui'i moi trutHig co gia in pH "-S pli moi Irui'mg anh huong tui hiC'u qua khu mau eua t.ic chung vi sinh v,^i, pli loi uu de loai bo mau nhieu lo^i ihutK nhuom thutmg irong iiguniic tu (> den III |5] Til kel qua nghien cim niiy, co the kel lu.m pli d-" ihieh h(,Tp cho hoat Jong khu mau thuoc nhupm Red I S2H1 cu.i chimg vi khuan V Bing Anh hiramg cua gia tri pH toi kha nang khu mau cua chijng vl khu^n A9 pli NAngd^thuAc